The world's second ranked team proved far too strong for their European opponents with a 9-0 victory at the NASPA Stadium in Narita City.

A three-run home run by left fielder Saki Yamazaki off Italy reliever Alice Nicolini ended the game one inning early in the bottom of the sixth due to the nine run margin.

The Asian side had led from start to finish after centre fielder Eri Yamada blasted a home run to left field on Greta Cecchetti’s first pitch.

They then scored again in the bottom of the third as Japan's star pitcher Yukiko Ueno did not concede a single hit.

Japan, Canada and Australia, the world's second, third and fourth-ranked sides, are all locking horns in Group B.

They are joined by China, Great Britain, Venezuela and Botswana as well as Italy.

United States, the world's top ranked team, have started as the favourites in a 16-team competition.

They are playing in Group A alongside fifth-ranked Chinese Taipei, sixth-ranked Puerto Rico, seventh-rated Mexico and eighth-ranked The Netherlands.

New Zealand, Philippines and South Africa complete the group.

The tournament winners will qualify for the Olympic Games in Tokyo, where softball is returning to the programme for the first time since Beijing 2008. 

Ten round-robin games are scheduled for tomorrow.